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Calculate the standard enthalpy of forma...

Calculate the standard enthalpy of formation of `CH_(3)OH(l)` from the following data:
`CH_(3)OH(l)+3/2O_(2)(g) rarr CO_(2)(g)+2H_(2)O(l), …(i), Delta_(r)H_(1)^(Θ)=-726 kJ mol^(-1)`
`C(g)+O_(2)(g) rarr CO_(2)(g), …(ii), Delta_(c )H_(2)^(Θ)=-393 kJ mol^(-1)`
`H_(2)(g)+1/2O_(2)(g) rarr H_(2)O(l), ...(iii), Delta_(f)H_(3)^(Θ)=-286 kJ mol^(-1)`

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Verified by Experts

Aim`: C(s) + 2H_(2)(g)+(1)/(2)O_(2)(g) rarr CH_(3)OH(l) , Delta_(r)H^(@) = ?`
Eqn.(ii) `+2 xx` Eqn. (iii) -Eqn. (i)gives the required eqn. with
`DeltaH = -393+2(-286) - ( -726 ) kJmol^(-1)= - 239 kJ mol^(-1)`
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